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  <script>
    var countSeniors = function (details) {
      let count = 0;
      details.forEach((item) => {
        if (item.slice(-4, -2) > 60) count++
      })
      return count
    };
    console.log(countSeniors(["7868190130M7522", "5303914400F9211", "9273338290F4010"]));
  </script>
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